A one-dimensional model for heat release rate and emission formation in diesel engines based on correlations for entrainment rate, lift-off length and ignition delay: Validation for transient conditions

Analysis of the indicator diagram is the basis of technical state evaluation of marine diesel engines. The indicator diagram contains a large amount of diagnostic information. A major problem for the diagnostic use of the indicator diagram is the pressure sensor location. Indicator channel and valve may introduce significant distortions in the resulting pressure. The paper presents results of research conducted on the medium speed laboratory engine Al 25/30. Pressure measurement (indication) was made by the sensor placed directly in the cylinder (instead of starting air valve), before the indicator valve (with special Kistler adapter) and on the indicator valve. Distortion of heat release characteristics for the sensor placed on the indicator valve is important, but it is estimated that diagnostic information is not erased. For medium speed engines is to be expected the use of a portable pressure sensors placed on the indicator valve. For this reason, further research is needed to assess the impact of channels and valves on different cylinders. During the research the course of heat release rate q and the heat released Q were determined. The curve of heat release rate q is a full equivalent to fuel injection pressure curve in the fuel pipes. It allows identification of the failure of the injection system. The curve of Q allows such determination and assessment of internal efficiency of the cylinder.

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A Phenomenological Combustion Model for Heat Release Rate Prediction in High-Speed DI Diesel Engines with Common Rail Injection

10.4271/2000-01-2933 ◽

2000 ◽

Cited By ~ 101

Author(s):

Christian Barba ◽

Christine Burkhardt ◽

Konstantinos Boulouchos ◽

Michael Bargende

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Diesel Engines ◽

High Speed ◽

Common Rail ◽

Combustion Model ◽

Rate Prediction ◽

Common Rail Injection

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Thermodynamic indexes of real driving conditions of gasoline and LPG fuelled engine

Archives of Transport ◽

10.5604/08669546.1225467 ◽

2016 ◽

Vol 40 (4) ◽

pp. 51-64

Author(s):

Ireneusz Pielecha ◽

Wojciech Cieślik ◽

Wojciech Bueschke ◽

Maciej Skowron

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Effective Pressure ◽

Engine Operation ◽

Transient Conditions ◽

Combustion Pressure ◽

Indicated Mean Effective Pressure ◽

Driving Conditions ◽

Additional Fuel

The aim of the conducted tests was to assess the method of delivering additional fuel dose in transient conditions and to determine the impact of this additional fuel dose on the engine operation conditions. The experimental tests were conducted in typical urban driving conditions. In the study was used system for indicating and acquisition of fast-varying data; the combustion pressure in the first cylinder of the 3-cylinder engine with spark ignition was measured, as well as the voltage on the petrol injectors and the liquefied petroleum gas injector. The post-processing analysis enabled defining engine operation indexes taking into account the aforementioned parameters. Also indicated mean effective pressure, the heat release rate and the amount of the heat released were analysed. In addition, the indexes of transient conditions of engine operation per one cycle were specified: change of the engine speed, of the maximum combustion pressure, of the indicated mean effective pressure and change of the heat release rate.

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Influence of hydrogen as a fuel additive on combustion and emissions characteristics of a free piston engine

Thermal Science ◽

10.2298/tsci181211071a ◽

2020 ◽

Vol 24 (1 Part A) ◽

pp. 87-99

Author(s):

Mohammad Alrbai ◽

Bashar Qawasmeh ◽

Sameer Al-Dahidi ◽

Osama Ayadi

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Ignition Delay ◽

Combustion Characteristics ◽

Fuel Additive ◽

Compression Ignition ◽

Piston Engine ◽

Free Piston ◽

Free Piston Engine

It has been shown that using fuel additives play an important role in enhancing the combustion characteristics in terms of efficiency and emissions. In addition, free piston engines have shown capable in reducing energy losses and presenting more efficient and reliable engines. In this context, the objective of the present work is to investigate the effect of using hydrogen as a fuel additive in natural gas homogeneous charge compression ignition free piston engine. To this aim, two models have been iteratively coupled: the combustion model that is used to calculate the heat release of the combustion and the scavenging model that is employed to determine the in-cylinder mixture state after scavenging in terms of its homogeneity and species mass fractions and to obtain the finial pressure and temperature of the in-cylinder mixture. In the former model, the 0-D approach through Cantera toolkit has been considered due to the fact that homogeneous charge compression ignition combustion is very rapid and the fuel-air mixture is well-homogenous, whereas in the latter model, 3-D-CFD approach through AN-SYS FLUENT software is considered to ensure precise calculations of the species exchange at the end of each engine cycle. The effect of hydrogen as a fuel additive has been quantified in terms of the combustion characteristics (e. g., ignition delay, heat release rate, engine overall efficiency and emissions, etc.). It has been shown that hydrogen addition reduces ignition delay time, decreases the in-cylinder peak pressure, while allowing the engine to operate with higher mechanical efficiency as it has high heat release rate, increases the NOx emission levels of the engine, but decreases the CO levels

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Investigating Combustion Process of N-Butanol-Diesel Blends in a Diesel Engine with Variable Compression Ratio

Clean Technologies ◽

10.3390/cleantechnol3030037 ◽

2021 ◽

Vol 3 (3) ◽

pp. 618-628

Author(s):

György Szabados ◽

Kristóf Lukács ◽

Ákos Bereczky

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Compression Ratio ◽

Release Rate ◽

Ignition Delay ◽

Alternative Fuels ◽

Internal Combustion Engines ◽

Combustion Process ◽

Injection Angle ◽

Combustion Properties

The search for alternative fuels for internal combustion engines is ongoing. Among the alternatives, plant-based fuels can also be mentioned. Alcohol is not a common fuel for diesel engines because the physical and chemical properties of the alcohols are closer to those of gasoline. In our research, the combustion properties of diesel-n-butanol mixtures have been investigated to obtain results on the effect of butanol blending on combustion. Among the combustion properties, ignition delay, in-cylinder pressure, and heat release rate can be mentioned. They have been observed under different compression conditions on an engine on which the compression ratio can be adjusted. The method used was a quite simple one, so the speed of the engine was set to a constant 900 rpm without load, while three compression ratios (19.92, 15.27, and 12.53) were adjusted with a fuel flow rate of 13 mL/min and the pre-injection angle of 18° BTDC. Blending butanol into the investigated fuel does not significantly affect maximal values of indicated pressure, while much more effect on the pressure rising rate can be detected. Furthermore, heat release rate and ignition delay increased at every compression ratio investigated. Despite the low blending rates of butanol in the mixtures, butanol significantly affects the combustion parameters, especially at high compression ratios.

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Optimized heat release rate for enhanced thermal efficiency under NOx, noise and peak firing pressure constraints in light-duty Diesel engines

Proceedings - Internationaler Motorenkongress 2017 ◽

10.1007/978-3-658-17109-4_13 ◽

2017 ◽

pp. 209-226 ◽

Cited By ~ 1

Author(s):

Jean-Marc Zaccardi ◽

Frédéric Nicolas ◽

Jordan Rudloff ◽

Gaetano De Paola

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Diesel Engines ◽

Thermal Efficiency ◽

Light Duty

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Diethyl Ether as an Ignition Enhancer for Naphtha Creating a Drop in Fuel for Diesel

ASME 2016 Internal Combustion Engine Fall Technical Conference ◽

10.1115/icef2016-9324 ◽

2016 ◽

Cited By ~ 1

Author(s):

R. Vallinayagam ◽

S. Vedharaj ◽

S. Mani Sarathy ◽

Robert W. Dibble

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Ignition Delay ◽

Cetane Number ◽

Cylinder Pressure ◽

Auto Ignition ◽

Peak Heat Release Rate ◽

Ignition Characteristics ◽

Ci Engines

Direct use of naphtha in compression ignition (CI) engines is not advisable because its lower cetane number negatively impacts the auto ignition process. However, engine or fuel modifications can be made to operate naphtha in CI engines. Enhancing a fuel’s auto ignition characteristics presents an opportunity to use low cetane fuel, naphtha, in CI engines. In this research, Di-ethyl ether (DEE) derived from ethanol is used as an ignition enhancer for light naphtha. With this fuel modification, a “drop-in” fuel that is interchangeable with existing diesel fuel has been created. The ignition characteristics of DEE blended naphtha were studied in an ignition quality tester (IQT); the measured ignition delay time (IDT) for pure naphtha was 6.9 ms. When DEE was added to naphtha, IDT decreased and D30 (30% DEE + 70% naphtha) showed comparable IDT with US NO.2 diesel. The derived cetane number (DCN) of naphtha, D10 (10% DEE + 90% naphtha), D20% DEE + 80% naphtha) and D30 were measured to be 31, 37, 40 and 49, respectively. The addition of 30% DEE in naphtha achieved a DCN equivalent to US NO.2 diesel. Subsequent experiments in a CI engine exhibited longer ignition delay for naphtha compared to diesel. The peak in-cylinder pressure is higher for naphtha than diesel and other tested fuels. When DEE was added to naphtha, the ignition delay shortened and peak in-cylinder pressure is reduced. A 3.7% increase in peak in-cylinder pressure was observed for naphtha compared to US NO.2 diesel, while D30 showed comparable results with diesel. The pressure rise rate dropped with the addition of DEE to naphtha, thereby reducing the ringing intensity. Naphtha exhibited a peak heat release rate of 280 kJ/m3deg, while D30 showed a comparable peak heat release rate to US NO.2 diesel. The amount of energy released during the premixed combustion phase decreased with the increase of DEE in naphtha. Thus, this study demonstrates the suitability of DEE blended naphtha mixtures as a “drop-in” replacement fuel for diesel.

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